Position your ladder securely, near the center of one side of the house. Once near the gutter, measure the depth and profile of the gutter. This will be needed if you intend to purchzse the same type of gutter as the one currently on the house.
Record the depth and profile measurements on a piece of paper. determine what type of gutters are already installed.
Attach the tape measure to one side of the gutter, and measure from one end of the gutter to the other. Add a few extra inches, to go around corners. Repeat this process for all the remaining sides of the house.
Write the measurements down on a piece of paper.
Divide the total footage for each gutter measurement by 10, to figure out exactly how many pieces will be needed. Make sure to purchase an extra couple of pieces, in case cuts need to be made around corners.